Stone Age skull from Kenya reveals astonishing human diversity – “A partial human skull found at a site in Kenya suggests early humans living in Africa were incredibly diverse. The 22,000-year-old skull is not a new species and is clearly that of an anatomically modern human, but is markedly different from similar finds from Africa and Europe from the same time, the researchers said…. [T]he new findings suggest that during this early period of human history, Africa may have supported even greater human diversity, with small, offshoot lineages that no longer exist today….”

Division of labor by sex and age in Neandertals: an approach through the study of activity-related dental wear – “The study reveals that all individuals have cultural striations, but those detected on the adult females are longer than the striations found in adult males. Regarding the distribution of dental chipping, the prevalence of this trait is higher in the maxillary dentition of males whereas females have the majority of dental chipping on their mandibular teeth. T he differences detected on the overall activity-related dental wear pattern denote a difference or a division of labor by age and sex in Neandertals while using the mouth as a third hand, i.e., in activities other than the provisioning of food, and provide new evidence for the lifestyle of this Pleistocene fossil human species.” – h/t paleogenomics!

Y chromosomes and Catalan surnames – “‘By genotyping 17 Y-STRs and 68 SNPs in ~2500 male samples that each carried one of the 50 selected Catalan surnames, we could determine sets of descendants of a common ancestor, the population of origin of the common ancestor, and the date when such a common ancestor lived. Haplotype diversity was positively correlated with surname frequency, that is, rarer surnames showed the strongest signals of coancestry. Introgression rates of Y chromosomes into a surname by non-paternity, adoption, and transmission of the maternal surname were estimated at 1.5−2.6% per generation, with some local variation. Average ages for the founders of the surnames were estimated at ~500 years, suggesting a delay between the origin of surnames (twelfth and thirteenth centuries) and the systematization of their paternal transmission. We have found that, in general, a foreign etymology for a surname does not often result in a non-indigenous origin of surname founders; however, bearers of some surnames with an Arabic etymology show an excess of North African haplotypes.'” – @dienekes’.

Elevated germline mutation rate in teenage fathers [pdf] – “We observe, as expected, that the overall mutation rate for fathers is seven times higher than for mothers. Also as expected, mothers have a low and lifelong constant DNA mutation rate. Surprisingly, however, we discover that (i) teenage fathers already set out from a much higher mutation rate than teenage mothers (potentially equivalent to 77–196 male germline cell divisions by puberty); and (ii) ageing men maintain sperm DNA quality similar to that of teenagers….” – h/t andrew sabisky! jayman tweeted: “8.2% false paternity rate in West Africans and 1.3% in Middle Easterners in this sample.”

Low IQ ups risk of heavy drinking among men – “The researchers analysed data collected from 49,321 Swedish males born during 1949 to 1951 and who were conscripted for Swedish military service from 1969 to 1971. IQ results were available from tests performed at conscription, and questionnaires also given at conscription provided data on total alcohol intake (consumed grams of alcohol/week) and pattern of drinking, as well as medical, childhood and adolescent conditions, and tobacco use. Adjustments were made for socio-economic position as a child, psychiatric symptoms and emotional stability and the father’s alcohol habits. ‘We found that lower results on IQ tests in Swedish adolescent men are associated with a higher consumption of alcohol, measured in both terms of total intake and binge drinking,’ Sjolund said.” h/t ruta akula!

Cads and dads – “Promiscuity and fidelity seem to be specific biological adaptations. Their manifestations in men and women are not as different as you might expect.” (whatever’s gotten into the economist these days?)

Sex Differences in Preferences for Humor: A Replication, Modification, and Extension [pdf] – “[M]en prefer women who are receptive to their humor whereas women prefer men who produce humor. These findings held even after we modified Bressler et al.’s questionnaire for better conceptual validity. Furthermore, using a separate measure designed to assess trade-offs, we found that men viewed humor receptivity as a necessity and humor production as a luxury when they were asked to create an ideal long-term partner. For women, it was just the opposite.”

What does it say about Owen Jones that he isn’t interested in scientific research? – “What I find irritating about progressive politics is that it ignores and contradicts science, while at the same time pretending to be in favour of reason. The entire worldview is based on the tabula rasa idea of human nature which is contradicted by science. The blank slate makes the progressive goal of equality of outcomes possible; indeed, if equality is not achieved there can only be nefarious forces at work and ‘more work to be done’.” – from ed west. see also Fancy a job in academia or the media? Best brush up on the new political correctness – “[Political correctness is] a faith, and it does not matter how daft the belief systems of a faith appear to a rational mind; if its critics sound backwards and out of touch and rural – literally ‘pagan’ – it will succeed.”

Why science is so hard to believe – “Science appeals to our rational brain, but our beliefs are motivated largely by emotion, and the biggest motivation is remaining tight with our peers. ‘We’re all in high school. We’ve never left high school,’ says Marcia McNutt. ‘People still have a need to fit in, and that need to fit in is so strong that local values and local opinions are always trumping science. And they will continue to trump science, especially when there is no clear downside to ignoring science.'”

Islam Is Not a Religion of the Book – “By this, I mean that as a whole humans are prone to accepting the primary causal role of reflective cognition, of beliefs avowed and rationales offered. We are confident in our conscious self control, despite a robust body of cognitive psychology which implies that much of our cognition is not under the control or constraint of rational faculties. This problem is particularly extreme among intellectuals, the very class which also attempts to understand human phenomena. Through the simple process of introspection and extrapolation intellectuals tend to reduce human action to the outcome of ratiocination, inference from eternal axioms. This is wholly inadequate to a phenomenon as complex as religion.” – from razib.

Old India’s Village of Warriors Becomes Birthplace of Bouncers – “Look closely and it becomes clear that the bouncers are all of a single physical type, their chests and biceps built like the front bumper of a sport utility vehicle. If they look like cousins, it is because they are. A startling number of them share a family name, Tanwar, and when the nightclubs close many will return to the same nearby village, a place where women walk down dusty lanes with their faces obscured by a cloth, balancing stacks of dried cow dung on their heads, much as their ancestors did three centuries ago…. The musclemen from the village of Fatehpur Beri are the descendants of the original inhabitants of the city, a genetic line that fortified itself over the course of centuries as they defended their village against waves of invaders on their way to the seat of empire. The sons and grandsons of cow and goat herders, they were born in an outpost surrounded on all sides by croplands. As Fatehpur Beri was swallowed by the expanding city, its spartan strongmen continued to train in the traditional way, stripping down to loincloths and wrestling in a circle of mud. But they were forced to look for a new line of work. ‘There is an element of the warrior in the Tanwars,’ said Ankur Tanwar, who opened the village’s first gym about a decade ago. ‘We fought with the Muslim invaders. We fought with the Britishers.'”